The effect of ESR of the capacitors on modeling of a quadratic boost converter

In recent years, the development of new technologies is requiring power supplies with wide conversion voltages. An alternative solution is to use a quadratic boost converter with a single active switch. This converter has two LC filters; thus, it will exhibit fourth-order characteristic dynamics. In this paper, switched linear, nonlinear averaged and linear averaged models are developed for the aforementioned converter. These models contain the effect of equivalent series resistance (ESR) of the capacitors. It is shown that inclusion of this effect in the corresponding transfer functions will produce damping to the first and second resonant peaks. The above will, in turn, simplify the controller design for either current or voltage mode control. At the end, experimental data for a 43 W quadratic boost converter will be given using a frequency response analyzer.